Device and process for applying gripping handles on packaging films, and shrinkwrap packer provided with such a device

Abstract

The present invention concerns a device ( 1 ) for applying gripping handles (M) on films (P), being supplied on shrinkwrap packers ( 2 ) for making bundles of bottles (B), cans and/or similar containers (B). The device ( 1 ) comprises: an applying head ( 10 ) provided with a roller ( 11 ) for applying gripping handles (M); an abutment mechanism ( 14 ) for operatively supporting a series of heat-shrinkable packaging films (P), being supplied on a respective shrinkwrap packer ( 2 ). The applying roller ( 11 ) and the abutment mechanism ( 14 ) are mobile with respect to one another between a non-operating condition, in which they are spaced apart, and an operating condition, in which the applying roller ( 11 ) is arranged, at the abutment mechanism ( 14 ), against at least one of the films (P) being supplied to apply a respective gripping handle (M) on the latter. The abutment mechanism ( 14 ) comprises a supporting tape ( 15 ) having an advancement surface ( 16 ) for advancing the films (P), which, in the operating condition, provides an abutment for the applying roller ( 11 ), which applies each handle (M) on a respective packaging film (P), acting against the advancement surface ( 16 ) of the supporting tape ( 15 ).

The invention claimed is: 
     
       1. Device for applying gripping handles on heat-shrinkable packaging films, being supplied on shrinkwrap packers for making bundles of bottles and/or cans, the applying device comprising:
 at least one applying head provided with at least one roller for applying a plurality of gripping handles supplied in the form of a continuous tape and subsequently cut into sections; 
 at least one abutment mechanism for operatively supporting a plurality of packaging films in the form of a continuous tape and subsequently cut into sections, optionally heat-shrinkable, being supplied on a respective shrinkwrap packer on which the applying device is mounted, the roller for applying of the applying head and the abutment mechanism being movable with respect to one another between a non-operating condition, in which the roller for applying of the applying head is spaced apart from the abutment mechanism, and an operating condition, wherein the roller for applying of the applying head is arranged, at the abutment mechanism, against at least one of the packaging films being supplied for applying a respective gripping handle on such packaging film, 
 wherein the abutment mechanism comprising at least one supporting tape, higher than the width of the packaging films being supplied, having an advancement surface facing, at least partially, the applying head for advancing the packaging films being supplied on the shrinkwrap packer, the advancement surface of the supporting tape providing, in the operating condition, an abutment for the roller for applying of the applying head, the roller for applying of the applying head applying a gripping handle on each packaging film being supplied, against the advancement surface of the supporting tape; and 
 wherein the supporting tape extends according to a ring-shaped development, substantially triangular, the supporting tape being movably actuated according to the same advancement direction of the packaging films being supplied on the shrinkwrap packer for carrying these packaging films in advancing along the applying head. 
 
     
     
       2. Device according to  claim 1 , wherein the supporting tape is provided with:
 at least one moving roller, operatively engaged to the supporting tape on the opposite side with respect to the advancement surface, the moving roller movably actuating the supporting tape according to the advancement direction of the packaging films being supplied on shrinkwrap packer; 
 a first idle roller operatively arranged upstream of the moving roller in the advancement direction of the packaging films being supplied, the first idle roller engaging the supporting tape on the opposite side with respect to the advancement surface; 
 a second idle roller, operatively arranged downstream of the moving roller in the advancement direction of the packaging films being supplied and engaging the supporting tape on the opposite side with respect to the advancement surface, the moving roller being interposed between the roller for applying of the applying head and the idle rollers, whereby the ring-shaped development of the supporting tape has a abutment rounded vertex arranged at the applying head and two transmission vertices spaced apart from the applying head and defining a base of the supporting tape having a ring-shaped triangular development. 
 
     
     
       3. Device according to  claim 2 , further comprising a counter-roller operatively active on the advancement surface of the supporting tape at the first idle roller or at the second idle roller, the counter-roller pressing the packaging films being supplied against the advancement surface of the supporting tape being moved to ensure the adhesion of the counter-roller, of the packaging films and of the supporting tape. 
     
     
       4. Device according to  claim 3 , wherein said advancement surface of the supporting tape has:
 a first flat rectilinear section defined between the first idle roller and the moving roller; 
 a second flat rectilinear section defined between the moving roller and the second idle roller, the packaging films being supplied being free to translate, along the advancement direction, with respect to the advancement surface of the supporting tape between the first and second idle rollers, in the operating condition. 
 
     
     
       5. Device according to  claim 2 , comprising:
 a first compensation chamber, provided with a plurality of transmission rollers movable with respect to one another, operatively arranged upstream of the first idle roller, in the advancement direction of the packaging films being supplied on the shrinkwrap packer, for compensating for the velocity and/or stretch variations at which the packaging films are subjected during the application of the gripping handles between the non operating condition and the operating condition; 
 a second compensation chamber, provided with a plurality of transmission rollers movable with respect to one another, operatively arranged downstream of the second idle roller, in the advancement direction of the packaging films being supplied on the shrinkwrap packer, for compensating for the velocity and/or stretch variations at which the packaging films are subjected during the application of the gripping handles, between the non operating and the operating condition. 
 
     
     
       6. Device according to  claim 2 , wherein the moving velocity of the supporting tape can vary between a minimum limit, at which ends of corresponding joining adhesive portions of each gripping handle being applied adhere to the respective packaging film, and a maximum limit, at which the packaging film is not superimposed to the gripping handle being applied or corresponding to the central area of the gripping handle being applied, the maximum limit being variable to take up different values greater than the minimum limit.